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Must Read....PSA for Windsor Roller block guys

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175K views 115 replies 63 participants last post by  408foureye  
#1 ·
There is a cracking problem that is becoming an epidemic, and its only among the 351 roller blocks, the F4TE. We are averaging 2-3 cracked blocks for every 10 we get in. The crack is in the same spot every single time.

The cracks are noticed easily by eye when you remove the number 2 and number 4 cam bearing. Its not a coincidence that this is the same area that is used for the spider tray hold down. You can clearly see the cracks in the picture.

A problem will arise if this crack runs, the cam bearing will lose press and the bearing will walk out quickly and its all down hill from there.

I can guarantee alot of shops will use the block, whether they overlook it or think its not a big deal. I do NOT use these blocks. If you are having your roller windsor block machined, tell your machinist you want to see this area, protect yourself.

I will answer all questions should you have any :)

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#4 ·
No idea what causes them, its odd because the roller 302 has the same design and I do not see the cracking like the 351.

I haven't had any failures, but if a guy wants to chance it and throw 600-700 hp through the block and twist it up, I guarantee the crack will run
 
#7 ·
Isn't it all the 351 Roller blocks? Making me scared. Is it possible to see the crack with the cam bearings installed? I was already planning for a Dart block over this next winter.
 
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#14 ·
so a motor with lower hp should be safe?
 
#17 ·
Just out of curiocity Woody- Is there anything you can do to further prevent a good block from cracking in this area? I figure the cam journals are hard to get to for chamfering...?
 
#19 ·
My block is from a 93, not sure if lightning or not. I did a full inspection before assembling mine and found no cracks. Fingers crossed mine doesnt crack.
 
#21 ·
So under 600 hp should be alright?????
 
#25 ·
What are the chances that a block without the crack will develope the crack when rebuilt to double or even tripple the 200hp that some are developing cracks at?

Does this concern you when sending out engines that you know will be up in that power range?

Thanks!
 
#23 ·
Hey Woody, what blocks are you using for your 408-418 strokers?
 
#27 ·
No it doesnt concern me, if these block that have 100k miles on them dont already have the crack, they wont develop them IMO. I believe the crack is a result of the environment in which these engines are used. Buses, trucks, vans etc.. How many hired drivers simply just keep driving them when the temp gauge is pegged? Once it overheats and wont run then they pull it over call a tow truck.
 
#28 ·
Woody - in post 23 you said you give them to your scrap guy. Yet in post 25 you responded to a question about what blocks you use to build strokers, and you said "F4 or earlier". Are you saying you still use these blocks and only send the cracked ones to your scraper?

Your post came just in time for me. My F4TE was at the machine shop getting freshened up for my 408. I mentioned this issue and asked them to inspect this area thoroughly. Thanks Woody.

I agree with your analysis - drivers of "fleet/work" vehicles abuse them.
 
#29 ·
Interesting. Never ran into a problem with one but it's something I'll sure check for from now on.
 
#30 ·
Yes I give the cracked ones to my scrap guy, the non cracked ones I use, like any other stock block. I see more of these blocks than 99% of guys in there entire lifetime, so it took a bit to see a pattern form.
 
#33 ·
Run it till it blows up. Enjoy it while it lasts. C'est la vie!